1. Field of the Invention
The present invention relates generally to a method for synthesizing magnetic core-semiconductor shell nanocrystals, and in particular, to magnetic core-semiconductor shell nanoparticles with high crystallization degree, uniform size, and high chemical stability and a manufacturing method thereof.
2. Description of the Related Art
Magnetic nanoparticles are applicable to various fields such as high-density magnetic recorder, sensor, and catalyst owing to their possibility for chemical synthesis. Particularly, magnetite (Fe3O4) nanoparticles occupy a singular position in the field of magnetic materials owing to their special physiochemical properties. Many researches have been conducted for physical phenomena such as charge ordering, mixed valence, and metal-insulator transition known as the Verwey transition.
As recent researches in bioscience become active, magnetite including other forms of iron oxide nanoparticles has been highlighted for biomedical applications owing to its exceptional biocompatibility.
Researches for coating magnetic nanoparticles being capable of controlling a position by the magnetic field with materials performing a specific function to make a core shell structure have been actively conducted.
Particularly, in the case where magnetic nanoparticles are coated with semiconductors, they incorporate the functions of catalysis, enhanced photoluminescence, protective layers, enhanced processibility, engineered band structures, improved stability against photochemical oxidation, and conjugation layers with biological molecules. Such magnetic-semiconductor core-shell structures can have magnetic properties, semiconductor properties, physical properties of inorganic and organic materials, and versatile functions ranging from metallic to dielectric materials. The magnetic-semiconductor core-shell structure is expected to deliver various potential functionalities in areas such as high-density data storage, biomedical applications, magnetic refrigeration, catalysts, and ferrofluids.
Cadmium selenide (CdSe) is a highly efficient luminescent semiconductor quantum-dot material. It is anticipated that the fusion of these two materials into a core-shell nanostructure should produce a new nanostructured material which retains the optical and magnetic properties of respective components, providing synergistically enhanced performance and functionalities which go beyond those of the individual components.
Thus, there is a demand for manufacturing Fe3O4/CdSe core-shell nanoparticles applicable to bio-separation, bio-manipulation, bio-assaying, vector delivery, and specific detection owing to their optical element sensing and magnetic actuation. For the same reasons, there is a demand for manufacturing magnetic-semiconductor core-shell nanoparticles such as Fe3O4@CdTe, Fe3O4@CdS, CoPt@CdSe, and FePt@CdSe.
Further, there is a demand for a technology for manufacturing magnetic-semiconductor core-shell nanoparticles having high crystallization degree, uniform size, and high chemical stability for enhanced applications and having both magnetic and semiconductor properties.